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Will hotter, drier landscape replace lush meadows?

There’s a reason they call it Paradise.

The wildflowers on Mount Rainier’s upper meadows are heavenly. Butterflies drift from bloom to bloom, and shy little rabbit relatives called pikas play hide-and-seek among the rocks.

In the distance, mountain ridges fade to the horizon in ever paler shades of blue, making it easy to imagine you’re looking down on all creation.

Elli Theobald spends a lot of time in Paradise, lying in perfumed beds of flowers, counting blooms and using tiny pipettes to extract nectar.

For the past five years, she’s spent every summer there, from the time the snow melts in the spring until it arrives again in the fall.

Theobald is a University of Washington biologist doing research on the effects of climate change. She monitors changes in pink heather, lupine, phlox, avalanche lilies and 45 other meadow plants in 75 research plots on the mountain.

Her mother and father brought her to Paradise as a child, Theobald said, and they were the ones who first got her interested in the flowers. Now she’s building her career on them.

“In many ways it’s a dream job,” she said. “I’m in the lucky position to be able to call documenting these changes ‘work.’ ”

The bad part of the job, she says, is that she’s almost certainly documenting the meadows’ demise.

Theobald expects the data that she’s recording to become a baseline for climate changes that, in the next several decades, will force the meadows out of existence.

Research indicates that higher temperatures are drawing trees upward into the meadows. When the forests shade the meadows out, the flowers and butterflies and pikas will have nowhere to go but up, where there’s not enough soil for them to survive.

“By the end of the century, I picture this being more like some California landscapes that are brown in the summer,” Theobald said. “The snow will probably melt a month and a half earlier, and it will be hotter and dryer — mostly rock with little vegetation.”

HABITATS VULNERABLE

Alpine and subalpine meadows are among the habitats in Mount Rainier National Park that are most vulnerable to climate change, according to Theobald and other researchers.

But if temperatures continue to rise as predicted, scientists say, life on the mountain will change from top to bottom.

The predicted temperature increases don’t sound like much — just 3.8 degrees by the 2040s and 6.8 degrees by the 2080s.

But researchers say even such small changes will upset the delicate timing on which plants and animals depend, leading to extinctions, invasions of non-native species and disease outbreaks.

Temperature effects as subtle as changing a bird’s breeding schedule could have consequences that ripple through the ecosystem, they say.

As the timing of winter freezes and spring thaws shifts, some plants and animals evolved for specific climatic niches on the mountain could face extinction.

Mount Rainier’s high meadows support seven of the 12 imperiled or rare plants in the park.

Gerald Rehfeldt, an ecological geneticist with the U.S. Forest Service, concluded in 2006 that because of climate change, most of the park will have a different mix of plants and animals by 2090, a conclusion accepted by a panel of scientists studying likely consequences of climate change at Mount Rainier.

The report, titled the Mount Rainier National Park Natural Resource Condition Assessment, calls Rehfeldt’s conclusion “general enough to be accurate.”

“The point is that the changes that are coming with the rates of CO2 (carbon dioxide) in the atmosphere will have a profound effect on the native vegetation,” Rehfeldt said. “In most cases this means that the communities will shift greatly.”

As the mix of plants changes, the animals that depend on them will have to change, too.

“It’s all about habitat,” said Mason Reid, a wildlife ecologist at the park who retired this year. “For most terrestrial animals, it won’t be the case that they are unable to withstand a few degrees of change one way or another, but that the habitat they depend on will change.”

The commonly held idea that animals will be able to simply pack up and move to more suitable habitat elsewhere on the mountain is not realistic for many species, he said.

“In many cases, there’s nowhere for them to go,” Reid said.

Because of its great height, he said, Mount Rainier is essentially a habitat island in the Pacific Northwest. As elevation on the mountain increases, temperatures fall, which creates rings of different life zones encircling the mountain.

Reid says climate change will push the rings higher on the mountain.

“At the upper end, as the snow and ice retreats, you don’t have soil, basically,” he said. “The advance of trees will probably outpace the soil-formation process.”

ANIMAL LIFE

In the Arctic, the polar bear is the poster child for global warming. On Mount Rainer, the pika is a good candidate for the role.

Pikas are warm and fuzzy fur balls about the size of guinea pigs. They’ve evolved to thrive at high altitudes and are highly sensitive to air temperature. Exposure to unusual heat for just a few hours can cause them mortal stress.

“They depend on vegetation in the high meadows,” Reid said. “If that changes, it will reduce their food supply.”

Another animal that depends on mountaintop conditions is the white-tailed ptarmigan, a chicken-size bird that changes color with the seasons. Ptarmigans camouflage themselves by turning white in winter to blend with snow and gray in the summer to blend with rocks.

Scientist believe Mount Rainier’s ptarmigan might be a distinct subspecies, and the U.S. Fish and Wildlife Service is considering adding them to the threatened species list.

The Cascade red fox, a candidate for the state’s endangered list, is at risk as well.

Mount Rainier has its own subspecies of red fox and its existence is tenuous. Scientists believe higher temperatures will bring a competitor — lowland red foxes — into their range and also coyotes, which are fox predators.

“If their range changes and there are interactions between the two,” Reid said, “the foxes are going to lose.”

AQUATIC LIFE

Lower on the mountain, warmer weather and changes in the timing of rainfall will disrupt life in ponds, wetlands and rivers, researchers say.

Climate models suggest that by mid-century, snow in the park will melt three to four weeks earlier than now, and that the amount of water in rivers and streams will be substantially lower.

“That’s likely to cause earlier drawdown and reduced water level, which would cause loss of habitat for some amphibian and wetland plant species,” said the park’s plant ecologist, Lou Whiteaker.

Birds rely on wetlands for food and nesting habitat, as do beavers, muskrast, skunks, minks, river otters and shrews.

“The climate change they’re predicting, along with storms of bigger intensity and precipitation at different levels, are all going to affect aquatic species — including fish and invertebrates — because of changes in water quality, temperature and sediment loading,” Reid said.

More sediment in streams, caused by debris flows or heavier rains, will interfere with fish breeding.

Changes in freezing and thawing patterns will change the mix of algae, bacteria and other tiny organisms in lakes, Reid said.

“We’ll see a changing distribution of nutrients in lakes, which will also affect anything that’s dependent on these nutrients,” he said.

Mount Rainier is home to eight species of native fish, two of which — Chinook salmon and bull trout — are listed as threatened under the Endangered Species Act. Another two — coho salmon and coastal cutthroat trout — have been proposed for listing.

FOREST AND FIRE

Mount Rainier’s iconic forests also are at risk, according to plant ecologists. Higher temperatures and longer dry seasons will increase insect infestations and disease and create longer and more intense fire seasons.

Warmer winters will allow more insects to survive the cold season.

Forest fires, currently rare at Mount Rainier, could become much more common.

Studies at the University of Washington indicate that by the 2080s, the area of forest burned in the Northwest each year will quadruple from the average of 2 million acres burned each year over the past century.

On Mount Rainier, whitebark pine trees, a candidate for protection under the Endangered Species Act, are especially at risk.

As temperatures rise, stands of white bark pine on Mount Rainier are increasingly being infected by blister rust, an invasive species to which they have little resistance.

Also, mountain pine beetles, previously restricted by temperature to lower elevations, have begun infecting trees higher on the mountain. Researchers worry that warmer weather will let the beetles produce two generations in the same growing season, a situation already occurring in Canada.

“When hit twice in a season, more trees would die,” Reid said. “The combination of rust and the beetle would put more stress on species that’s now a candidate for Endangered Species Act.”

The effects wouldn’t stop there, Reid said.

Unlike most conifers, whitebark pine seeds don’t spread by floating through the air. Instead, they depend on animals to disperse them.

If the trees disappear, so will the birds and squirrels that depend on them for high-energy food.

“Clark’s nutcracker are totally dependent on white bark pine,” he said. “If we lose the whitebark pine, then we lose the Clark’s nutcracker. It’s all interrelated.”

ACCELERATED CHANGE

The issue with global warming is not change, said park biologist Barbara Samora. Mount Rainier is a dynamic environment and change is constant.

What has researchers concerned, she said, is that this episode of climate change is not natural and that it’s happening at an unnaturally high speed — too fast for normal adaptive processes.

“With climate change, theoretically, changes will be accelerated,” she said. “Native species won’t have time to evolve quickly enough to adapt.”

That makes it difficult to watch, even for scientists trained to maintain a detached perspective.

“It would be a different thing if you could say, ‘This is natural. This happens. It gets warm and it gets cool,’ ” said Theobald, the flower researcher. “But the rate at which it’s warming now, there’s no way it’s naturally caused.”

“I try to keep a scientific distance,” she said, “but sometimes I get kind of a panicky feeling and wonder, ‘What are we doing to this earth?’ ”

“I can’t help feeling bad that my baby’s kids won’t be able to experience this.”

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